Canadian Journal of Public Health

, Volume 97, Issue 4, pp 283–285 | Cite as

Drugs and Driving

When Science and Policy Don’t Mix
  • Mark AsbridgeEmail author


This commentary briefly looks at the Canadian federal government’s proposed legislation to strengthen the enforcement of drug-impaired driving, placing special emphasis on cannabis. After outlining the legislation, three issues are examined. Of primary concern is at what level cannabis use impairs driving ability leading to an increased risk of motor vehicle collision. Current epidemiological evidence is reviewed. Equally important is the government’s emphasis on the training and implementation of Drug Recognition Experts (DREs), specially trained police officers whose role is to detect drivers under the influence of drugs. Research on the effectiveness of DREs is discussed, along with a dialogue regarding the potential shortcomings of the DRE program. Finally, a brief surveillance of international policy literature on drugs and driving is offered, along with some sober thoughts on the potential difficulties that may emerge in the enforcement of the proposed legislation.

MeSH terms

Cannabis motor vehicles public policy police 


Il est question, dans ce commentaire, du projet de loi du gouvernement fédéral canadien visant à renforcer les sanctions contre la conduite avec facultés affaiblies par les drogues, et en particulier le cannabis. Après avoir décrit le projet de loi, les auteurs examinent trois enjeux. Tout d’abord, il est important de déterminer le niveau de consommation de cannabis qui affaiblit l’aptitude à conduire et fait augmenter le risque d’accident de la route; les preuves épidémiologiques actuelles sont examinées. Un autre enjeu tout aussi important est l’accent du gouvernement sur la formation et le déploiement d’experts en reconnaissance de drogues (ERD), des policiers ayant reçu un entraînement spécial et dont le rôle est de déceler les conducteurs sous l’emprise des drogues. Les études de recherche sur l’efficacité des ERD sont présentées, ainsi qu’un dialogue sur les carences éventuelles d’un programme d’ERD. Enfin, les auteurs donnent un bref aperçu des publications internationales sur les politiques contre l’intoxication au volant et font quelques réflexions objectives sur les obstacles possibles à l’exécution de la loi proposée.


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Copyright information

© The Canadian Public Health Association 2006

Authors and Affiliations

  1. 1.Department of Community Health and EpidemiologyDalhousie UniversityHalifaxCanada

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